Various linear solvers (either via normal equations, QR, etc.) all have really fast multi-threaded implementations in, e.g. OpenBLAS. These could directly bene

Various linear solvers (either via normal equations, QR, etc.) all have really fast multi-threaded implementations in, e.g. OpenBLAS. These could directly benefit lm() and glm(). That said - there's no reason why you couldn't already call out to these (multithreaded) libraries with (single threaded) R.